William Henry Chamberlin (February 17, 1897 — September 12, 1969) was an American historian and journalist. He was the author of several books about the Cold War, Communism and US foreign policy, the most famous of which was The Russian Revolution 1917-1921 (1935). Chamberlin wrote the book whilst stationed in Russia between 1922-34 as the Moscow correspondent of The Christian Science Monitor.

Chamberlin was born in Brooklyn and educated in Pennsylvania schools and later at Haverford College. At the age of twenty five he moved to Greenwich Village and was deeply affected by the cultural bohemianism and Bolshevik politics there. He worked for Heywood Broun the book editor of the New York Tribune. He also published under the pseudonym of A.C. Freeman and was a socialist pacifist, albeit one who supported the Communists in the USSR. (von Mohrenschildt 1970).

He arrived in the Soviet Union as a young man and soon found work with the Christian Science Monitor, for which he would work until 1940. He also acted as Moscow correspondent for the Manchester Guardian. He was, initially, a Marxist and a sympathizer with the Communist revolution. During his stay, he changed to being a critic. His first book, Soviet Russia, published in 1930, detailed the policies of the New Economic Period and was, on the whole, supportive of the changes brought by the Revolution. However, even early on he had his doubts. Toward the end of his stay, he became convinced of the errors of Communist policy. He and his wife Sonya, who was Russian-born but whom he met in the US where she and her family had immigrated, visited the Ukraine and the North Caucusus during 1932-33 and witnessed the famines that were being produced by forced collectivization (von Mohrenschildt 1970).

After leaving the USSR, he went to Germany and his experiences with Nazism further convinced him of the dangers of collectivism and absolutism in general. He became more convinced of the importance of individual rights and of the value of the United States Bill of Rights. He was posted by the Monitor to East Asia and wrote Japan Over Asia based on what he learned there about Japanese militarism. He was transferred then to France (von Mohrenschildt 1970).

After returning to the US, he lived in Washington, DC and then in Cambridge, Massachusetts. Much of his later work was aimed at criticizing communism, socialism and collectivism in general. He continued to write both scholarly books and more popular articles. His The Confessions of an Individualist was an autography published in 1940 shortly before his collaboration with Russian Review, a connection that was to last until his death from a stroke twenty eight years later (von Mohrenschildt 1970).